Method of and apparatus for taking photographs



May 25 1926.

H. L. COOKE METHOD 0F AND APPARATUS FOR TAKING PHOTOGRAPHS Filed June 28, 1922 `LISSGWTL 5 Sheets-Shed?. l

May 25V 1926. 1,586,071

` H. 1 ,.cooKE METHOD OF AND 'APPARATUS FOR TAKING PHOTOGRAPHS Filed June 28. 1922 5 sheets-sheeffs Arme/VHS May 25 1926.

H. L. COOKE METHOD OF AND APPARATUS FOR TAKING PHOTOGRAPHS Filed June 28, 1922 5 Sheets-Sheet 4 #u l( :l- /A/VENTOH 4 TTOR/VEYS May 25 1926.l

1,586,071 H. L. cooKE METHOD OF AND APPARATUS FOR TAKING PHOTOGRAPHS Filed June 28, 1922 y 5 Sheets-Sheet 5 ,i 1' ATTORNEYS Patented May 25, 192s.

UNITED `s'r'arns- PATENT," oFFlcE- HEREWARD LESTER COOKE, OF PRINCETON, NEW JERSEY, ASSIGNOB TO AERO SURVEY GORP., A CORPORATION OF DELAWARE.

'METHOD 0F AND APPARATUS FOR TAKING PHOTOGRAHS.

Application led June 23, 1922. ,Serial Nb. 571,510.

rIhis invention relates to cameras and particularly to ,cameras suitable for taking time exposures ot objects moving relatively to the camera. The invention is thus of 5 particular l importance for securing photographs from aircraft, particularly photo graphs suitable for purposes of photograminetry.

One of the prime objects of the invention consists in rendering lenses covering an extremely wide field of view suitable for aerial photography. Such wide angle lenses being slow in action, require a considerable period ot exposure for the production ot a properly exposed photograph.

The present invention provide means whereby the image of the landscape which is being photographed may be -held still on the'sensitized medium tora period of 0 time, even though the aircraft from which the exposure is being made is in motio'i. `With this object in view, the invention contemplates to provide a camera. the sensitized medium and lens of which may he moved in relation to each other in the direction of line of flight-ot` the aircraft, the speed and direction o't the movement being such that the movement ot the imagewhich is caused bythe apparent shifting of 3 the landscape*is exactly compensated, so that during the time of exposure the image remains xed on the sensitized medium. A well defined photograph of extremely wide angle and long exposure may thus be ob-4 5 tained.

The invention further. contemplates the provision of a telescope associated with the camera and in which the cross-hairs and objective are subjected to the same relative 3 motion as the sensitized medium and obje-1:-

tive of the camera. The purpose of this telescope is to enable the operator to make i the necessaryr adjustments to. bring about thedesired relative motion above referred to. i When the desired adjustments have been made, the image of the landscape as viewed through the telescope will remain fixed with reference to the cross-hairs of the telescope. and the operator may then proceed to take the photograph.

The invention further-.provides gyrostatic mechanism whereby the camera may be placed under neutral gyrostatic control so that the axis of the camera will not be effected by small 'irregularities in the flight ofthe air-craft. The invention further contemplates `a mechanism whereby the sensitized medium or film of the camera is carried by supports independent ofthe said gyrostatic system, so that when the iilm ispassed lengthwise throughthe Camera-as by being unrolled from one reel and wound'upon'another -reel-the position of the center of mass of the gyrostatic system will not be -disturbed by the change of weight fromv one reel to the other.4

A good understanding of the above and certain other features and objects of the invention may now be had from "the following description of certain specific forms of embodiment thereof, reference being had to the accompanying drawings, in which: Figure 1 is a View illustrating the camera and its mounting in front elevation;

Figure 2 is a plan view of Figure 1; Figures 3 and 4 are left andright side yelevations of Figure 1:

Figure 5 is a 'detail-view, partly in section, showing the movable kfilm support ot' the camera;

Figure G is a view showing a's'ection of Figure 1, on line VI` VI, looking in the direction of the arrows;

' Figure 7 is a perspective view of the cam indicated in Figure 6;

Figure 8 is a bottom .plan view of the camera;

Figure 9 is a view illustrating the bracket 37 carrying the cross-hairs of the telescope and illustrating the range of movement thereof with relation to the telescope, various positions of which are indicated in dotted lines;

Figure 10 is a detail view of the frame 7 5 carrying'identifying registration marks for the film;

Figure 11 is a View showing a positive print from a film, illustrating the registration marks appearing thereon;

Fig-ure -12 is a detail viewshowing a suction back mechanism whereby the film is sccured to the film support 25; l Figure 13 4is a bottom plan view of Figure 12;

Figure 14 is a view similar to Figure 4,

Liz:

showing a modil'ied form of the apparatus, part of the mechanism, namely the gimbal mounting andthe gyrostat, having been omitted for sake of simplicity;

Figure 15 is a vieW showing the camera and telesco Y e of Figure 14 in right side elevation; and l Figure 16 is e.` View showing a bottom plan view of Figure 15.

Similar characters of reference designate similar parts in each of the several views.

The present formy of instrument as illustrated in `Figure/s1 lto 6,- consists of a mounting comprising a ring 1, which by means of supports 2, is secured to the Hoor 3 of thel aircraft. Suitable shock-absorbing devices Such as springs are preferably interposed in su ports 2. These devices, however, are not i lustrated in the drawing, to avoid unnecessary confusion.

Revolvably mounted on ring 1 is a inember 41 comprising a pair of uprights en' and a ringportion 4;", Which, as illustrated in section in Figure 1, is arranged to revolve on ring 1. A gimbal trame 5 is rotatably mounted on the uprights 1i by means ot trunnions t5. The anis T-T oi these trunnions constitutes what will be rei-erred to as the transverse gimbal axis. .et member 8 is rotatably mounted in girnbal trarne 5 on trunnions 9, the airis 10u10 of which constitutes what is herein referred to as the ore and ai't gimbal axis, which intersects with the transverse gimbal airis 7 7. The member@ is composed of a ring 8a having depending extensions 8b joined by a transverse support 8C, all the parts ot member 8 orming a rigid unit.

Across the upper ends ont extensions 8b is ecured transverse member 11 vf ich con to and supported by the extensions Si o the member 8. The camera lens, shown in Figs. 8 and 16, is placed Within the lens guard 14d and preferably has its axis coincident with the axes of the, motor 12 and gyrostat Wheel 13, which common axis will hereinafter be referred to as the camera axis. A shutter 14g (Fig. 8) is provided in the lens guard, and mechanism 14h comprising a liexible cord or other suitable device is provided for 'actuating the same.

The camera back 141 y(see particularly Fig. 6), has two hollow pockets 14e, and a rod 15 parallel to the fore and aft giinbal axis 10-10 extends through the pockets 14e and through a lug 144, and is free to slide longitudinally therein. A single-turn screw cam 21 (Fig. 7) is firmly secured to the Worm Wheel 2O and is thus free to rotate with the Worm wheel about rod 15. A pin 23 firmly secured in the rod 15 is maintained in firm sliding contact with the screw-shaped end of cam 21 by the action of the spring 19. Rotation ot' rod 15 is prevented by means of an arm 15 rigidly mounted thereon (see Figure 6), and having an opening' through which extends a pin 15b mounted in one or the lugs lil o'l' the camera body. By virtue ot this connection, arm 15 is free to slide on the pin 15b so as to permit of the reciprocal move ments of the rod. Rotation ol' the rod, however, is prevented.

' i motor 22, the speed of which may be controlled by electrical apparatus, indicated diagrammatically by C in Figure 1, is secured to the back 14h o the camera in suchmanner that the shaft 2e thereof operates the Worin *.rbeel 20. 'on orina4 el st. .v 21, Where@v treme 'f The if/cle ot mor@ The 'eed or' tor 22 is indica by a s itable device 100 connected to the motor r1' mounted on .the supporting men y the number or reciprocations or the rod is indicated by the saine indicatingl device intl, which is a :torni ot combined speed indicator and revolution counter.

A film support 25 with it-s plane normal to the camera airis, is provided with a pair or" lugs 26 through which the rod 15 is fitted, relative motion between the film support and the rod being prevented by a set screw 27. A third lugI 28 on the film support 25 at the opposite side of the camera from the lugs 26, has a flat lower end so that this side of the film support is slidingly supported on a rod 29 arranged parallell to the and film support 25 will undergo a uniform motion of translation parallel to the plane` ofthe film support and'normal to the axis of the camera,.this uniform motion being interrupted at lntervals, as hereinbefore explained, by the return of the film support a strip of territory.

25 to its original position. By adjusting the speed of the motor, the above-mentioned uniform motion of the film support may be regulated to the speed desired.

Two film boxes 30 4rigidly supported on the member 4 by means of supports 31, are arranged to contain reels 30 for the exposed and unexposed film. Flexible lighttight .bellows 32e`nab1e the film to be passedI through the top 1lib of the camerafrom one filmpocket30 to the other, the film passing through the grooves 33 (Figure 5), in the film holder and occupying the positionlshown at the dotted line 34 in the focal plane of the camera lens. It should here be noted that by virtue of the abovedescribed arrangement the center of mass of the gyrostatic system is prevented -from being changed as the film is passedfrom one film box to the other. vAlso that the flexible bellows 32 will not impose any appreciable angular,constraintl about the axes 7--7 and 10-10 between the gyrostatically stabilized camera, 14- and the fuselage of the aeroplane, provided, as will in general be the case, that the aeroplane is flying comparatively` steadily during the photographing of For obvious reasons, these are important features of the present form of construction.

The film holder 25 is provided with a device well known in the art, such as a suctio'n back, which insures that the part of the film in they film support 25 shares the hereinbefore-described4 intermittent motion of the said support. Such mechanism is illustrated in Figs. 12 and 13, in which' the holder 25 is shown as provided with an interior hollow space 150 which is connected by a flexible tube 151 to a source of suction.

The lower surface of the holder is provided with a number of perforations 152 which communicate withl the chamber 150 and which therefore cause the film to bey drawn snugly against the surface of the holder,

' Whenever the suction is applied. Control of the suction may be effected bya suitable I further provide mechanism indicated byA handles 301 for Winding the .film from the one film ,box to the other such mechanism being preferably adapted automatically to advance the film by the proper amount to bring an unexposed portion into the field 'of view of the photographic objective, and also mechanism for providing sufiicient slack in the film on both sidesl of the film holder to take up the intermittent motion.A The latter mechanism, being Well known in connection with moving picture machines, is not illustrated, in. order to prevent unnecessary complications of the drawing.

A level 47, preferably filled with a very l viscous liquid, such as glycerine, is mounted on transverse member' 1la to indicate when the average position of the camera axis is approximately vertlcal over an mterval'of time.v Any other suitable device for indieating verticality maybe employed.

A telescope 34, arranged preferably with its axis parallel to the camera axis, is'rigidly-'attached to the camera. body 14 by means of the bracket 35, and to the transverse member 11EL by means of the bracket 36, so that .the telescope and camera axes are maintained in fixed relation. f

The object glass of the telescope 34 is chosen with an equivalent focal length identical with that of the camera lens. bracket v37 passes slidingly through a slot 37Min the walls of the telescope 34 transversely to the axis thereof, and carries cross Wires 38 (Figs. 2 and 9) in the focal plane of the object glass of the telescope, said wires being arranged parallel to the axes 7-7 and 10-10 of the camera mounting. The bracket 37 is rigidly attached to one of the lugs 2G of the film holder 25, as shown in'Figure 5, and passes slidingly through a slot, parallel to the rod 15, in the Wall of the camera back 14h, the sliding connection with saidwall being made light-tight b v suitable means, such as the flange'39 shown in Figs. 5 and 1 and 3. The intermittent motion imparted to film support 25 by the motor 22 is thus shared by the cross-hairs 28, so that'an operatorviewing through the eyepiece of the telescope 34 anl object to be photographed, may determine any movement of the image cast by the camera lens on the film in. the film holder 25 by observing the corresponding movement of the image formed by the telescope object glass relative to the cross Wires 38. When the telescopic image is still with reference to the cross Wire 38, the photographic image i is at rest on the film, and a com paratively 10410. The camera then forms part of a gyrostat system under neutral accelerationai les control. Means for adjusting the frictional forces on the bearings of the trunnions 6l and 9 are provided in the form, for example, of friction screws 40 and 41, as shown. rEhe frictional forces produced by these screws are so adjusted that chance nutational disturbances imparted to the gyrostat'system will be rapidly damped out. This frictional control is not to be made so great, however, that the small irregularities in the motion of the aircraft will result in appreciable precessional disturbances being imparted to the gyrostatic system. Experiment has shown that this is feasible.

A clamping device 42, (Figs. 2 and 4) is mounted securely on the ring 4 and consists of the standard 44 in which a handle 46 and jaws 45 are rotatably mounted. By means of the-handle 46 the jaws 45 may be engaged or disengaged with the rings 5 and 8a. The camera axis will thus be fixed with respect to the aircraft when the jaws are in the engaged position, and will be under neutral gyrostatic control when the jaws are disengaged. yl`he clamping jaws 45 are intended to lock the position of the camera with respect to the aircraft when the latter is banking on turns, or encountering air bumps, and also to bring the camera axis back to the approximate vertical when it becomes displaced from any cause.

The camera is fixed in the aircraft with the fore and aft gimbal axis 10-10 in the fore and aft direction, and with the spring- 19 toward the bow of the aircraft. En 'this position, the uniform, but discontinuous, motion of the film holder 25 is in directien forward with respect to the aircraft.

rThe floor of the aircraft is provided with apertures 50 and 5l (Figs. and 2) to aliow the camera and telescope unobst' L i i being arcuateias i to allow for the angular ratus on supporting` ring The operation of the camera wifi. described. With the aircraft ily on its course and the motor stat wheel 13 operating high spe operator looks through the telescope and since the direction of the anis of the tetescope is approximately fined in space, observes that there is relative motion between the cross-hairs 88 and the image of the ground. He then angularly shifts the Whole apparatus, which is mounted rotatably on the ring i, until this relative motion occurs parallel to the fore and aft cross-wires of the telescope. He then starts the motor 22 and so controls its speed that the cross Wires 38 share the steady forward drift of the telescopic image of the ground to be photo graphed, the cross-wires intermittently snapping back, under the action, of the pa ne nesaovi spring 19, cam wheel 2 and motor 22, so that the intersection of the cross-wires B8 takes up, at regular intervals, new points of coincidence with the telescopic image of the landscape. `When the-angular adjustnient of the apparatus ony the ring 1, and the speed of the motor 22 have been adjusted to secure a satisfactorily steady` coincidence between the moving cross wires and the moving telescopic image, the camera is in adj ustnient and a time exposure of the film may be made, care being taken that the cross-wires are approximately in the middle of their run when the exposure is made, to avoid the danger of the film snapping back during the exposure.

Consideration will show that when the camera is in adjustment for making an eX- posure, the fore and aft gimbal axes must be parallel to the line of Hight of the air-craft relative to the ground, so that ifthe ring 4b has marked on it graduations 52 cooperating with a pointer on the ring l, Fig. l, the line of flight relative to the fore and aft axis of the aircraft may be determined.; rThe pilot is able, by means of his compass, to`

tell the magnetic bearing of the fore and aft axis of the aircraft, so that if in addition the reading of the pointer 53 on the scaie 52 is communicated to him, or automatically transferred tothe compass by suitable mechanical means, not shown, he may ascertain at any'instant the magnetic bearing of his line of flight relative to the ground, and so may adjust the line of flight to any prearranged magnetic bearing, provided the operator at the camera continues to`adjust the angular position of the ring 4b in the ring so that there is no transverse motion,

parallel to the transverse gimbal anis 7 3?, l

of the telescopic image of the ground Beit.- tive to tne cross wires 38.

` may loe shown it is the Tan-e frequency of reciprocation or i5 to the speed of revolution of the r 22, determined by intervening gears tance of travei of the cross Wires successive discontinuities of thai'. tei-mined bythe pitch 'J'Jhe screw g the equivalent focus of the teliff rom this expression it is seen that if a standard height 7L for navigation of the aircraft be chosen, the speed indicator portion of the combined speed indicator and revoluope and camera objectives; 7L the height L tion counter 100 connected to the 'shaft of the motor 22 may be calibrated to give the ground speed of the aircraft in, for instance, miles per hour, this speed being proportional to N lwhich is Athe only variable in the'expression, if the height h is kept constant, since R, d and f depend on the construction of the apparatus only. 'Furthermore, it may be seen that the ground distance traversed between successive discontinuities in the motion of the rod 15 is given by the expression lad.

so that the revolution counter portion of the combined speed indicator and revolution counter 100, when suitably geared, maybe made to indicate the ground distance traversed, in any suitable unit, say miles.

It thus appears that the apparatus described nia-y be adapted readily to determine the ground distance traversed b the aircraft, and the line and speed of flight, thus affording the pilot all the information'necessary to navigate aircraft by the method of dead reckoning. i

Furthermore it should be noted that if exposures made with this camera' are made with intervals of a chosen number of intermittent motions of the `shaft 15, indicated on lthe counter 101, the photographs will be evenly spaced on the landscape. Also they may be taken with the aircraft iying on a predetermined magnetic course, as hereinbefore explained, so that evenly spaced photographs may be taken covering a given tract of land ina predetermined manner, a matter of the utmost importance in practice.

One' of the most important features of the present invention consists in the fact that the present type of camera permits the employment of slow photographie lenses covering anextremely wide field of view. lt will be necessary in using such lenses, to have the aperture 50 in the floor of the aircraft, entirely open, and not covered with plate glass or mica, such as may be employed when moderate angle views are to be taken. The reason for this is that the rays forming the marginal portions ot extreme angle views will meet the plate glass or mica shield at very oblique angles, and will suer a prohibitive loss in intensity. For this reason a wind plou h 29, such as is indicated in Fig. 1, shoul be provided, to minimize disturbing gyrostatic ei'ects .due to the violent rush of air past the aperture 50. y

Also if extreme angle views are to be taken through a color filter, this filter should be incorporated as a unit with the camera lens, to avoid the loss of light in r.the oblique rays due to the introduction of additional reflecting and rcfractin surfaces. Methods of incorporating the lterl with the lens are de .rame,in the fore and aft direction.

scribed .in my co-pending application for Letters Patent on color filters, Serial Number 533,805- dated-.February 3, 1922.

lens relative to the film during exposure.

For, this purpose I provide a frame 75 (Fig. 10) which is mounted in the interior of the camera on supports 76 Fig. 5) close to the surface of the ilrn (indicated at 34). The frame is fitted with narrow registration indicators 56. The line joining these indicators bisects the rectangle formed by 'lie ne frame is also provided with pointed marl-1s 57, the line joining which bisects' the rectangle in the transverse direction. The axis of the camera lens meets the intersection of the lines joining the marks 56 and the mar 57, respectively. During an exposure the film will move relatively to the frame 75 which is fixed in the camera. The side indicators 57, therefore, will leavel blurred images on the film, as indicated in Fig. 11, in which the distance of movement' of the indicator extends from the apex point A to the apex point B. The apex C of the part of the film, exposure oi which is totallyv prevented by the side indicators, however, will be well defined. The indicators 56 will produce sharply defined marks E on the exposed lilm, which marks together with the apex marks C will serve in an obvious manner to locate the average position, during exposure, of the intersection oi the camera lens axis with the lm.

lt will haveA been observed that in the foregoing form of embodiment of the invention the desired relative motion between the camera objective and sensitized medium is produced by maintaining the lens or objective in fixed position and moving the sensitized medium. l't is within the scope of the invention, however, to produce the desired relative motion by maintaining the sensi tized medium in. fixed position and impressing the motion on the lens or objective, as described below.

A lt will also have been observed that in the foregoing form of embodiment the direction of the relative motion may be adjusted simply by turning the camera on its rotatable mounting, the angle through which the camera is turned being such that the direction 'of the motion is caused to be parallel to the line of lflight. instead of providing such rotatable mounting, however, the camera ma be mounted in the aircraft in fixed position and the desired parallelism of the said relative motion to the line of Hight may be secured by adjusting the direction of the said mot-ion with respect to the camera.

isa'

p lished, yis by impressing two movements at rlght anglesto each other simultaneously on the sensitized medium or camera lens and adjusting the speed of eaich movement so that. the resultant impressed motion is in the desired direction. Such a form of embodimentl is illustrated in Figures 14, 15 and 16, in which the camera 14 is mounted in a gimbal frame (not shown) correspondin in all particulars lto that of the previous orm of embodiment, with the exception, however, that the rotatable mounting comprised of rings 1 and 4 of the previous embodiment is omitted, so that the camera cannot be rotated about the vertical axis. The mechanism for impressing intermittent motion on the film support of the camera is omitted and an ordinary stationary iilm carrier is substituted therefor. If desired an ordinary plate and plate holder may be used instea of the film.

The objective or lens of the camera is fixed in a member 105 which is provided with tongues 106 whereby the same is mounted in a member 107 in such manner as to be capable of slidin movement in the direction of the fore an aft gimbal axis 10-10.

' The member 107 is similarly secured to the body of the camera 14 by tongues 108, so as to be capable of movement along the transverse gimbal axis 7 7. Motors 109 and 1.10 are mounted on the camera body and provided with cams 111 and 112- cooperating with cam followers 113 and 114, respectively, provided on members 107 and 105. Leaf springs 115 are provided to hold the camvfollowers in engagement with their cams and these cams are so formed that when they are made to revolve at a uniform speed, each member 105 and 107 is impressed with a uniform intermittent motion The speed of each motion may be adjusted independently of the other by means of electrical controlling mechanism Ka and Kb in the motor circuits. The motion vthus impressed on thev objective or lens mounted in the member 105 will be the resultant of two components, these components being adjustable independently of each other so that any desired resultant speed and direction of movement may be motion.,

The telescope in the present form of embodiment is vprovided with vfixed cross-hairs, and the objective or lens 117 of the telescope is made movable. The telescope lens is mounted in a bracket 116 xed to the member so that the movement to the objecl Lasaovl tive of the telescope is the same as that impressed on the objective of the camera.

The manner of using the present form of embodiment of the invention will now be readily understood. After the motor 12 and gyrostat wheel 1'3 have been set into rapid rotation, so that the camera .is placed under neutral gyrostatic control, vthe operator views the landscape through the telescope and notices the drift of the image thereof past the cross-hairs. 'He then starts one of the motors, say 109, and adjusts its speed until the drift along one of the cross-hairs, 38, is eliminated and thereupon starts the motor and adjusts its speed until the drift along the other of the cross-hairs, is eliminated. If necessary, he repeats the adjustments until the image of the landscape is entirely stationary relative to the cross-hairs,

and, therefore, relative to the sensitized medium. He then makes the time exposure. It should be noted, however, that owing to the fact that the instantaneous angular lpositions of cams 111 and 112 will ordinari y be subject to continual change, the objectives will snap back along the two axes at different periods, so that care must be taken Athat such reversal will not take place during the time interval of an exposure.

This form of camera may be adapted for the use of plates instead of films. It is obvious in both forms of camera shown in the drawings that the grooves 33 in the film support 25 may be enlarged sutlieiently to receive an ordinary photographic plate holder. In the first `form of camera exhibited, the plate holder inserted in the enlarged grooves 33 of the film support 25 will share the intermittent motion of the said film support, while in the form of camera shown in Figs. 14, 15 and 16, the plate holder will remain at rest, the suction back being of course omitted in both forms.

It will be observed that one of the important features of the'invention consists in the fact that the relative motion between the objective and the sensitized medium of the camera is periodically interrupted to effect the return of the said objective and sensitized medium to a given relative position. in view of this feature, exposures may be taken at any desired intervals of time, so that it will be possible. to secure overlapping photographs, showing parts of the same territory on adjacent exposures, a point of utmost importance in aerial photography, especially when the photographs are to be used for photogrammetry. Moreover, this feature of the invention renders it possible to transmit the same relative motion to the optical members of the sighting device, so that the photographer is enabled to determine whether or not the adjustment of the apparatus is such that-the image is stationary on the sensitized medium. Further advantages arisingfrom this feature of the invention consist in the fact that the fihn may be held perfectly flat by means of the suction back and that plates may be used as well as films.

Although I have herein shown and 'described only two specific forms of construction embodying the invention, it will be understood that many changes and modifications may be made therein without departing from the spirit and scope of the invent-ion, it being my intention to claim the saine broadly in whatever form its principles may be employed.

What I claim is: f

1. In combination, a camera adapted 'for use with an objective and sensitized medium, means for producing during exposure a relative motion between said objective and sensitized medium in a plane normal to the axis of said" objective, and means for adjusting the direction of said relative motion in said plane.

2. In combination, a camera adapted for use with an objective and sensitized medium,

means for producing during exposure a relative motion between said objective and sensitized medium in a direction. normal to the axis of said objective, anda rotatable mounting for said camera whereby the angular vposition of said camera is adjustable about its own axis.

3. In combination, a camera adapted for use with an objective and sensitized medium, means for producing-during exposure a relative motion between said objective and sensitized medium in a. plane normal to the axis of said objective,'means for adjusting the speed of said relative motion, and means for adjusting the direction ot said relative mov tion in vsaid plane.

4. In combination, a camera adapted for use with an objective and sensitized medium, means for producing during exposure a relative motion between said objective and sensitiaed medium in a direction normal to the axis of the saidL objective, means for adjusting the speed of said reiative motion, and a rotatable mounting for said camera whereby the angular position of said camera is adjustable about its own axis.

In combination, a camera adapted for use with an objective and sensitized medium,

means for producing during exposure a rela-` tive motion between said objective and sensitized medium in a direction normal to the axis of said objective', and means `tor periodically returning said objective and sensitized medium toa given relative position.

6. In combination, a camera adapted forA use with an objective and sensitized medium,

and mechanism for producingvduring eximechanism comprising means whereby said.

objective land -sensitized medium are periodically returned .to a given relative position.

7 In combination, a camera adapted for use with an objective and sensitized medium, means for producing during exposure a relative motion between said objective and'sensitized medium in a direction parallel to the y focal plane of said objective, and a sighting device associated with said camera.

8. In combination, a camera adapted for use with an objective and sensitized medium, means for producing during exposure a. relative motion between said objective and sensitized medium in a direction normal to the axis of said objective, a sighting device as,- sociated with said camera and comprising a plurality-of optical members movable in normal to the axis of said objective, said mechanism comprising means whereby said objective andsensitized medium are periodically returned to an initial relative position, a sighting .device associated with said camera and comprising a p'ui't'ality of optical members movable in relationl to each other, and means whereby corresponding relative motions are simultaneously .impressed on the said members of the sighting device.

IO. In combination, a camera. adapted for use with an objective and sensitized medium, means tor producing a uniform relative motion between said objective and sensitized medium in a direction normal to the axis of said objective, and a mounting pormitting freel relative motion between the axis of said camera and the patform upon which said mounting is supported.

ll. In combination, a camera adapted for use with an objective and sensitized inedium, means for producing during exposure a relative motion between said objective and sensitized medium iii a direction normal to the axis of said object-ive, and a mounting permitting free relative motion between the axis of said camera and the platform on which said mounting is supported.

12. In combination, a camera adapted for use with an objective and sensitized medium, means for producing uniform reiative motion between said objective and sensitized medium in a direction normal to .the axis of said objective., and a gyroscopic stabilizing device associated with said camera.

18. In combination, a camera adapted for Vuse with an objective and sensitized inedijum, means tor producing uniform relative ses motion between said objective and sensitized medium in a direction normal tothe axis of said objective, and a gyrostatic stabiliz-in device,` under neutral accelerational contro associated with said camera. i

14. In combination, a camera adapted for.v

16. In combination, a camera mountedtol permit a swinging motion of its axis, a receptacle for a sensitized medium, and means constituting a light-tight passage between said camera and receptacle permitting relative motion between said camera and receptac'e.

17. In combination, a camera mounted to permit a swinging motion of its axis, a receptacle for sensitized medium, and means constituting a light-tight passage between said camera and receptacle permitting relative motion between said camera and receptacle, saidA camera 4and receptacle being mounted so unit.

18. In combination, a camera under gyrostatic control, a'receptacle for sensitized me` dium, and means constituting a light-tight passage between said camera and receptacle permitting relative motion between camera and receptacle.- l

19. In combination. a camera under gyrostaticv control, a receptacle for sensitized inedium, means constituting a light-tight'j passage between the camera and receptacle per` mit-ting relative motion between` the two, and means for so mounting said camera and receptacle that the saine may be shifted as a unit.

20. In combination, a camera, a gimbal mounting therefor, a gyrostatic mechanism associated with said camera in-said mounting lwhereby said camera is placed under gyrostatic control, means for passing a nlm through the camera, said means comprising a plurality of reels for carrying the exposed and yunexposed portions of the` l'm, rcspecL tively, and means for supportingsaid reels independently of said giinbal mounting,

whereby the center of mass of said gyrof staticl syst-em is prevented from being dis turbed when said film is passed.A from'onc reel to the other.

that they may be shifted as a Lesson -means for producing during exposure a rela- 'tive motion between said objective and sensitized medium in a direction normal to the axis of said objective, and independent -means for advancing unexposed portions ot sensitized medium in the interval between exposures.

23. In combination, a camera, a suction plate for the support of sensitized medium, and means for shifting said suction plate in a direction parallel to its own plane.

24. In combination, a camera adapted for use with an objective, a suction plate, and means for producing unifonm relative motion between said objective and suction plate in a direction normal to the axis of said objective.

25. In combination, a camera adapted for use with an objective, a suction plate for4 the support of sensitized medium, and means for producing during exposure a relative motion between said objective and suction plate in a direction parallel to the plane ot said suction plate.

26. In combination, a camera adapted for use with an objective, a suction plate, and means for producing during exposure a relative motion between said objective and suction plate said means periodically restoring said objective and suction .plate to a given relative position.

27. In combination, a camera adapted for use with an objective and sensitized medium, means for producing during exposure a relative motion between said objective and sensitized medium in a direction normal to 4the axis of said objective, and means for iis sensitized medium, independently operated I the same movement on the optical members of the camera, and thereupon making the exposure. v

31. The method of securing a photograph of an object when the object and camera are `in motion relatively to each other, which consists in observing the object through a telescope comprisin manner that the image of the moving object appears to be stationary on the crosshair member, subjecting the sensitized member and objective mem-ber of the camera to the same relative motion, and exposing the sensitized member.

32. The method of securing a photograph of an object when the object and the camera are in motion relatively to each other, which consists in observing the object through a telescope comprising an objective and crosshairs, causing said objective and cross-hairs to move in relation to-each other so that the image of the moving object ap ears .to be stationary on the cross-hairs, su jecting the an objective member land cross-hair mem r, causing said members to move relatively to each other in such sensitized medium and objective of `the camera to the same relative motion, periodically interrupting said .relative motion to return the above-named optical. parts of the telescope and camera to a given initial position, and taking the exposure during a` period of said relative movement.

33. Apparatus for taking photographs from movingsupports such as aircraft coniprising a camera, mechanism for eliminating relative motion between the image of the landscape and the optical member of the `camera on which said image is produced comprising means for causing relative movement of the camera lens .and the sensitized medium forming such optical member of the camera, and means for marking said sensitized medium to indicate the average position of the camera lens relative to said medium during an exposure.

34. Apparatus for taking photographs from moving supports such as aircraft comprising a camera, mechanism for eliminating relative motion Ibetween the image of the landscape and the sensitized medium on which the image is produced, and means for marking said sensitized medium during an exposure to record acondition of the eX- posure caused by the operation of suchrelative motion eliminating mechanism, and means for marking said sensitized medium during an exposure to record a condition of ,the exposure caused by the operation of such relative motion eliminating mechanism.

In testimony whereof I have affixed my signature to this specification.

l HEREWARD LESTER COOKE. 

